1. Field of the Invention
The present invention generally relates to an apparatus for transferring liquids from one container to another and more particularly concerns an apparatus for transferring toxic liquids, such as pesticide, from a supply container to another container, such as a sprayer tank, that is capable of rinsing the supply container after the toxic liquid has been withdrawn therefrom.
2. Description of the Prior Art
Recent government regulations have provided that liquid pesticides must be handled with a transfer system that substantially eliminates the possibility of pesticide spillage during the transfer of the pesticides from their supply container to the holding tank of a sprayer. The regulations also provide that the transfer system must include means for flushing the pesticide container with water after the container has been emptied and for recirculating the rinse liquid either back to the sprayer tank or to some other vessel where it can be disposed of without contaminating the environment or otherwise becoming a source of danger to farm workers.
The known prior art pesticide transfer systems generally include a housing containing a pump, a measuring vessel, and a relatively complex arrangement of valves and switches. The systems include at least one set of suction and rinse hoses that lead from the housing to a nozzle assembly which is adapted to be detachably mounted in the closure of a pesticide supply container. A further hose extends from the housing to the sprayer tank to which pesticide is to be transferred and another hose leading between a rinse water container and the housing. Briefly stated, the user first manipulates the controls to pump pesticide from the pesticide container into the measuring vessel until a selected volume thereof is accumulated in the measuring vessel, as indicated by volumetric markings on a translucent section of the side wall of the measuring vessel. Thereafter, the user resets the controls and pumps the measured volume of pesticide from the measuring vessel directly to the sprayer tank. Finally, in the event the pesticide supply container has been emptied during the measuring operation, the user again resets the controls and pumps water from the water container through the rinse hose into the pesticide supply container to thoroughly flush the container and make it safe for disposal. During such rinsing step, the rinse water is usually pumped from the container to the sprayer tank.
In some of the prior known pesticide transfer systems, the nozzle assembly, commonly referred to as a rinse and suction probe, is fastened to the closure neck of the pesticide supply container so that it may be left attached until the pesticide container is emptied. After transfer, either the rinse and suction hoses are detached from the associated ports of the probe or a tube section of the probe is left in the supply can and a removable part of the probe is detached from the tube section. In such prior art systems, when a substantial volume of pesticide remains in the supply can after a transfer operation and it is desired to transfer a different pesticide from another supply can so that it is possible to mix said different pesticide with the pesticide already in the measuring vessel, the rinse and suction hoses or the aforesaid detachable part of the probe is detached from the partially depleted can, and the rinse and suction hoses or the aforesaid tube section is connected to the other supply can so that the different pesticide can be removed from said other can. To prevent spillage of the pesticide check valves are mounted either in the ends of the hoses or in the removable part of the probe.
From the foregoing description, it will be appreciated that the prior art pesticide transfer systems are subject to a number of shortcomings. Since all or part of the probe is left sealed within the closure of a pesticide can when pesticide is left in the can, the user must have several probes (or tube sections thereof) available if several pesticides are to be mixed and transferred to the sprayer tank. It will be recognized that such probes (or tube sections) are relatively expensive, and thus the requirement to have several probes available for multiple pesticide transfers makes the overall system considerably more expensive than a system which would employ only one probe.